The possibility to recover energy from the heat of the exhaust gas of e.g. motor vehicles becomes more and more attractive in view of increasing fuel prices. With the aid of so-called thermoelectric modules, it is possible to produce electric energy from the heat energy of the exhaust gas. In these modules, so-called thermoelectric elements convert a difference in temperature into an electric voltage according to the Seebeck effect. Such thermoelectric modules are usually composed of many serially connected thermoelectric elements and are on the market in the form of flat, thin and encapsulated units.
The more thermoelectric modules can be set in direct contact with the heat of the exhaust gas, the greater the yield of electric energy. Further, the larger the difference in temperature across the thermoelectric modules from the high-temperature side to the low temperature side, the greater the yield of electric energy. Accordingly, the configuration of the thermoelectric generator unit is of great importance.
It is the objective of the invention to provide a thermoelectric generator unit which offers a high yield of electric energy and has a compact construction.